Early Evening: Mix flour, salt, and instant yeast in a large bowl. Add the water and mix until just combined. Don't knead. Cover with a plastic wrap and leave it at room temperature for 12-18 hours.
Next Morning: Your dough will be quite sticky, don't freak out. Place it on a well-floured surface, also sprinkle the top with flour, and fold each side into the middle, repeat one time. Let it rest for 15 minutes.
Meanwhile, place a clean tea towel in a round bowl and dust with dark rye flour (or oat bran/all-purpose flour - use what you have at hand).
Shape Dough: Fold the dough again and shape it into a ball. Use more flour if needed. Transfer the dough into the bowl, seam side up, and sprinkle with dark rye flour. Cover with the tea towel and let it rise for 2 hours at room temperature.
Preheat Oven: Place a dutch oven with the lid on in the oven and preheat to 445 °F/230°C 30 minutes prior to baking.
Bake: Remove hot Dutch oven from the oven (be careful - don't burn yourself), tilt the bowl with the dough into the Dutch oven, pop on the lid, and bake for 30 minutes. Take off the lid and bake for another 15 minutes until golden brown.
Cool: Transfer the bread on a rack and let it cool before slicing.